This Sound-Proof Installation was Built Using Compressed Concrete and Bubble Wrap

An installation at the Karolinska Institutet in Sweden is made entirely of translucent concrete panels. Composed of concrete and bubble wrap, the site blends both high and low technology processes. This high-tech lecture hall is an amorphous space with unique acoustic qualities.

The panels were created by compressing High-Performance Concrete between two layers of Bubble-Wrap. With 262,500 cavities and 1,000,000 membrane-perforations, the material creates a diffused echo-free ambiance.

The million micro-perforations absorbs noise while the cavities diffuse high-pitch sounds. The shape of the structure also diffuses sounds in a lower register. The result is a totally unique noise-free environment. The structure's irregular bubble-like surface contrasts with the sterile lab environment that dominates the rest of the building. Brown terrazzo was chosen to simulate a mud-floor while the bubbles create an alienesque aesthetic. Together with the light refraction in the micro-layered glass railings, an almost surreal Alice in Wonderland atmosphere is created.

The casting boxes were produced using as little material as possible. Each of the 250 panels needed formwork made from twelve unique steel pieces. The form was then filled with a plastic granulate and hand-shaped to create the correct 3D surface. The granulate is re-used by the producer indefinitely.

Lectures are held on a 49 x 10 foot (15 x 3 meter) LED-Screen. Sound is distributed through the space using 68 microphones and 234 loudspeakers (61+129 in the small hall). Outside the installation, announcements and speeches can be made making use of the acoustics of the shell. The announcer can choose his/her position, in relation to the shell, depending on the size of the audience and the level of intimacy he/she wants to achieve.

Light artists, Svante Pettersson and Daniel Ljung created the lighting concept with dynamic LED lights installed both behind and in front of the panels. Clouds passing through the sky are the default lighting scenario, however, visitors can interact and change the lighting scenario via smartphone. With the lights off – the space takes on a more sombre atmosphere, resembling early charcoal drawings of Sofia Kanje.